Control apparatus for engine starters



Dec. 1, 1936. J B DYER 2,062,970

CONTROL APPARATUS FOR ENGINE STARTERS Original Filed Aug. 5, 1933 2 Sheets-Sheet l Dec. 1, 1936. J B DYER 2,062,970

CONTROL APPARATUS FOR ENGINE STARTERS Original Filed Aug. 5, 1933 2 Sheets-Sheet 2 \Nsssss:

rs. 3;3 M VQMSMM. M 04 Patented Dec. 1, 1936 UNITED STATES PATENT OFFICE CONTROL APPARATUS FOR ENGINE STARTERS Application August 5, 1933, Serial No. 683,748 Renewed August 8, 1935 32 Claims.

This invention relates to engine starter control devices of the type in which the starter is rendered operative by the closing of the ignition switch, is prevented from operating while the engine is running, and is automatically rendered operative again in case the engine stops with the ignition switch closed.

It is among the objects of the invention to provide a controller of this type which is simple in construction and reliable in operation. This object is accomplished in the disclosed embodiments thereof by an electromagnetic device which will cause the starting motor switch to be closed in response to closing the ignition switch and which is rendered ineffective to hold the switch closed in response to the over-speeding of the starting motor after completing the starting operation, and which is positively prevented from becoming effective again to close the switch by a device which is operative until the engine stops.

In one form of my invention, I employ a centrifugal switch responsive to the over-speeding of the starting motor to control the circuit of the winding of the electromagnetic device which operates to close the starter switch when the ignition switch is closed, thereby permitting the starter switch to open and thereafter to be positively held open until the engine stops. In another form of my invention, the electromagnetic device includes a winding acting difierentially with respect to the main exciting winding, said differential winding, during the starting operation, being insufficiently effective to prevent operation of said device to close the starter switch. When the starting motor overspeeds, this differential winding operates to cancel the effect of the main winding, and the starter switch is permitted to open.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred embodiment of one form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a diagram illustrating one form of the present invention.

Fig. 2 is a fragment of the diagram shown in Figure l, and shows the status of a portion of the apparatus during the engine cranking operation.

Fig. 3 is a view similar to Figure 1 showing the status of a portion of the apparatus during the running of the engine.

Fig. 4 is a wiring diagram illustrating a modified form of the invention,

Referring to Figure 1, designates an enginedriven generator connectible with a battery 2| through wires 22 and 23, and a connecting cutout relay 24. The shunt field winding 25 of the generator 20 is connected by a wire 26, ignition switch 21 and wire 28 with the battery 2|. Hence, the shunt field 25 is initially separately excited by the battery 2| in order to obtain the relatively rapid increase of the voltage as the speed of the generator is increased after the engine fires. The engine is cranked by starting motor 30 having a Bendix or inertia pinion 3i automatically engageable with, and disengageable from the flywheel gear 32 of the engine to be started. The shaft 33 of the motor 30 is connected by gears 34 and 35 with a shaft 36 carrying a centrifugal device 31 which'includes a sliding member 38 adapted to engage a non-conducting block 39 attached to a blade spring contact 40 normally engaging a contact 4|. The contact 40 is connected by wires 42 and 22 with the generator 20. In order that the engine starting motor 30 will operate automatically to crank the engine whenever the ignition switch 21 is closed there is provided an electromagnetic device which comprises a central magnetizable core cooperating with two external magnetizable members 51 and 52 providing pole pieces which respectively cooperate with armatures 53 and 54 attached to a rod 55, which is slidably supported by the core 56. The member 5! provides leakage gaps at 5Ia. A spring 56, interposed between the armature 53 and the core 50, normally supports the rod 55 in the position shown in Figure 1, wherein the armature 53 is held away from the magnetizable member 5| and armature 54 is held away from the magnetizable member 52 but within range of their influence. In this position of the rod 55 a movable switch contact 51 is held out of engagement with stationary contacts 58 and 59, connected respectively by wires 60 and SI with wire 23 and starting motor 30. The contact 57 is insulatingly carried by the rod 55 and is slidable along a reduced portion 55a thereof, and is maintained against the shoulder 55b thereof by a spring 5111 interposed between the contact 5'! and a plate 55a attached to the rod 55. The plate 55a is attached to the diaphragm 62 of a delayed action device which includes the diaphragm SZ and a chamber member 63 having a restricted vent 64. The magnetizable member 5| is magnetized by a winding 10 of relatively few turns of relatively heavy wire connected with the wire 26, and by wire it with the contact 4|. The magnetizable member 52 is magnetized by a magnet coil 12 of relatively fine wire and having a greater number of turns than the winding 10. The winding 12 is connected with the wire 1| and with ground at 13.

The operation of the device is as follows: The operator closes the switch 21, thereby causing current to flow from the battery 2| to the ignition apparatus (not shown) and also to flow through the magnet coil 10, the circuit of which includes the wire 26, wire 1|, switch contacts 40 and 4|, wire 42, wire 22, the armature of generator-20 and thence through ground to the battery 2|. The magnetism induced in the magnetic circuit including the parts 50 and 5| will be suflicient to attract the armature 53 against the action of the spring 56, thereby causing the contact 51 to engage the contacts 58 and 59, as shown in Fig. 2. When this occurs current will flow from the bat?- tery 2| to the motor 30 through thencircuit including the wire 60, contact 58, contact 51, contact 59 and wire 6|. The rotation of the motor shaft 33 causes the pinion 3| to be automatically connected with the engine gear 32 to crank the engine. When the engine fires the pinion will be automatically demeshed from the engine gear so that the starting motor may rotate free of the load of cranking the engine. The starting motor will therefore over-speed, thereby causing the centrifugal device to move the sliding member 38 against the block 39 and to separate the contact 40 from contact 4| thereby interrupting the path of low resistance from the battery 2| to the coil 10. Since the switch 40, 4| is opened the only way in which the circuit through the winding 10 can be completed is through the winding 12 which is of much higher resistance. Therefore the current flowing through the coil 10 is decreased to such extent that coil 10 is no longer eflective to hold the switch 51 closed against the action of spring 56. Due to breaking its short-circuit, coil 12 becomes efiective to move the armature 54 to the position shown in Fig. 3 and to hold the armature 53 substantially out of the field oi influence of the magnetizable member 5|. During the operation of the engine coil 12, which is then responsive to generator voltage, will hold the rod 55 in such position that the contact 51 can never be closed with the contacts 58 and 59. The engine must come to rest before the coil 12 will release the armature 54 to permit the rod 55 to descend by gravity to normal position shown in Fig. 1. If the ignition switch 21 is still closed, the operation of the starting of the engine will be repeated, since the switch contact 40 is then in engagement with the contact 4|, the starting motor being at rest.

Reference is now made to Fig. 4 disclosing a modified form of the invention. An engine driven generator I20, which charges the storage battery |2I and is connected therewith through a cutout relay I22, is provided with a shunt field winding I23 whichis connected by wire I24, switch I25 and wire I26 with a wire I21 connecting the relay I22 with the battery I2I. Hence when the switch I25 is closed the field winding I23 is excited .by .the battery I2I. Hence, the generator voltage will rise more rapidly at the start than would be the case ii the field I23 were connected between the generator and relay I22. The switch I25 also controls the ignition apparatus (not shown) connected with the wire I24.

The vehicle engine which drives the generator I20 is started by means of an electric motor I30 which is connected with the fly wheel gear I3I of theengine to be started through a Bendix or inertia pinion drive including a pinion I32 Which is meshable with the engine gear |3I and is threadedly connected to a shaft I33 driven by the motor. The switch for connecting the battery I2I with the motor I30 includes a stationary contact I40 connected by wire |4| with wire I21, a movable contact I42 and a stationary contact I43 connected by wire I44 with the series field winding I45 of the motor and thence through the motor armature.

The device for automatically closing the starter switch-when the ignition switch I25 is closed in order to start the engine and for automatically opening the starter switch when the engine starts comprises an electromagnetic structure including a central tubular core I50 associated with a magnetizable member |5| providing pole pieces I52 and having leakage gaps I 53 at the upper end of the core I50. The pole pieces I53 cooperate with an armature I54 mounted on a rod I55, the reduced upper end |55a of which provides a support upon which the contact I42 is relatively slidable but is insulated therefrom The rod I55 provides a shoulder I55b against which the contact I42 is normally urged by spring I56 confined between the contact I42 and a disc I51 secured to the upper end of the rod I55 and also secured to a flexible diaphragm I58 which cooperates with a cup-shaped member I59 to provide a motion retarding chamber I60 vented by a restricted orifice I6I. The armature I54 is held in a normal position shown in the drawings by spring I65 confined by the armature I54 and the core I50. The core I50 is associated also with an external magnetizable body I10 providing pole pieces |1I which cooperate with an armature I12 mounted on the lower end of the rod I55.

The magnetic structure including the core I50, the magnetizable member I5I and the armature I54 is influenced by two magnet coils I80 and I8I, the former being of relatively few turns of relatively coarse wire and the latter of a larger number of turns of relatively fine wire. The electromagnet structure comprising the core I50, the magnetizable member I10 and the armature I12 and is influenced by a magnet coil I82. The magnet coil I80 is connected with the wire I24 and by wire I83 with a connection I84 between the series field winding I45 of the motor and its armature. The coil I8| is connected between coil I80 and ground. The magnet coil I82 is connected by wire I85 with the generator at a point between the generator and cutout relay I22 and the winding I82 is grounded.

The operation of the form of the invention shown in Fig. 4 is as follows: When the switch I25 is closed to connect the ignition with the battery I2I, current will fiow from the battery through wire I26, switch I25, wire I24, coil I80, wire I83 through the armature of motor I30. Part of the current flowing through the coil I80 will also flow through the coil |8I which is wound differentially with respect to the coil I80. But, since the resistance of the path through wire I83 and the armature of motor I30 is much less than the resistance of the coil I8I, coil |8| will receive a relatively small amount of current; and, though the coil I8I opposes the magnetizing effect of the coil I80, the opposition will not be suflicient to prevent the coil I80 from energizing its associated magnetic structure sufiiciently to attract the armature I54 downwardly to cause the contact I42 to engage the contacts I40 and I43. Then current will flow from battery I2I.

wire I21, wire I4I, contact I40, contact I42. contact I43, wire I44, series field winding I45 and the armature of the motor I30. The motor will operate automatically to connect the pinion I32 with the fly wheel gear I3I of the engine to be started and thereafter to crank the engine. When the engine becomes self-operative the pinion I32 will be automatically demeshed from the engine gear I3I. The motor I30, being then freed of its load of cranking the engine, will speed up very rapidly thereby causing the motor to generate in its armature an E. M. F. which will cause the ampere turns of the coil I to diminish and the ampere turns of the coil I8I to increase. This results in the magnetizing effect of the coil I8I substantially balancing the magnetizing effect of the coil I89, sufliciently, at least, to permit the spring IE5 to move the armature I54 away from the poles I52 thereby causing the switch contact I42 to be separated from the contacts I46 and I43 thereby interrupting the circuit through the starting motor.

The generator being initially excited by the battery, the voltage of the generator will rapidly increase as the engine picks up speed after becoming self-operative. Therefore, the coil I82 will receive sufiicient current to energize its associated magnetic structure and cause the armature I12 to move toward the poles I'II thereby positively holding the armature I54 away from the field of influence of its associated electromagnet and hence positively holding the motor switch in open position so that during the running of the engine it cannot be closed again. Even at a very low speed there will be sufiicient current flowing through the coil I82 to seal the armature H2 in the upper position, thereby preventing any possibility of closing the starting motor circuit.

In both forms of the invention the delayed action device, provided by a diaphragm and chamber having a restricted vent ISI, prevents too rapid descent of the movable contact of the starter switch so that, in the event the engine turns momentarily at a speed approximating zero speed, the starter will not be brought into action. The delayed action device functions, in case the engine fails to remain operative after having been started, to permit the starting motor to come substantially to rest before the starting operation is repeated.

It is therefore apparent from the foregoing description of the construction and mode of operation of two forms of my invention, that said invention embraces an electromagnet for drawing the movable contact of the starter switch into engagement with stationary contacts, an instru ment responsive to the overspeeding of the motor for rendering'said electromagnet inoperative to maintain said movable contact in circuit-closing position, and means responsive to engine operation for positively maintaining the movable contact in circuit-open position. More specifically my invention embraces a second electromagnet responsive to generator voltage for positively maintaining the armature of the first electromagnet out of the field of influence thereof so long as the engine is operating. In the first form of my invention the ampere turns of the coil of the first magnet are reduced by a centrifugal switch operated in response to the overspeeding of the motor. In the second form the ampere-turns of the coil of said first magnet are cancelled by the ampere-turns of a second coil responsive to an E. M. F. of the motor armature when over-speeding.

While the form of embodiment of the present invention as herein disclosed, constitutes a pre ferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means responsive to overspeeding the starting motor for weakening the influence of said coil to permit opening of starter switch and means responsive to engine operation for positively holding the starter switch in open position.

2. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means including a centrifugal switch responsive to over-speeding the starting motor for reducing the ampere turns of said coil to permit opening of the starter switch, and means responsive to engine operation for positively holding the starter switch in open position.

3. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means including a second electromagnet coil responsive to E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampere-turn eifect of the first coil to permit opening of the starter switch, and means responsive to engine operation for positively holding the starter switch in open position.

4. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means including a centrifugal switch responsive to over-speeding the starting motor for reducing the ampere-turns of said coil to permit opening of the starter switch, a generator for charging the battery and means responsive to generator voltage for positively holding the starter switch in open position.

5. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connccting said coil with the battery, means including a second electromagnet coil responsive E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampereturn effect of the first coil to permit opening of the starter switch, a generator for charging the battery and means responsive to generator voltage for positively holding the starter switch in open position.

6. An engine starter control system comprising, in combination, a battery, a starting motor, a

starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating themovable contact of the starter switch, a switch for connecting said coil with the battery, means responsive to overspeeding the starting motor for weakening the influence of said coil to permit opening. of starter switch, a generator for charging the battery and means responsive to generator voltage for positively holding the starter switch in open position.

7. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch having a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature tobe retracted from its electromagnet and the switch to open, and means responsive to engine operation for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

8. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch having a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means including a centrifugal switch responsive to overspeeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted from its electromagnet and the switch to open, and means responsive to engine operation for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

9. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch having a movable contact, an electromagnet for closing the starter switch and including a coil and amovable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means including a second electromagnet coil responsive to E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampereturn effect of the flrst coil thereby permitting said armature to be retracted from its electromagnet and the switch to open, and means responsive to engine operation for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

10. An engine starter control system comprising. in combination, a battery, a starting motor, a starter switch having a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means including a centrifugal switch responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted from its electromagnet and the switch to open, a generator for charging the battery and means responsive to generator voltage for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

11. An engine starter control system comprising, in combination, a battery, 9. starting motor, a starter switch having a movable contact an electromagnet for closing the starter switch and including a coil and a movable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means including a second electromagnet coil responsive to E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampere-turn effect of the first coil thereby permitting said armature to be retracted from its electromagnet and the switch to open, a generator for charging the battery and means responsive to generator voltage for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

12. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch having a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature connected with the movable contact of the switch, a switch for connecting the coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted from its electromagnet and the switch to open, a generator for charging the battery and means responsive to generator voltage for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

13. An engine starter control system comprising, in combination, a battery, 0. starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch to open, and means acting directly upon said rod in response to engine operation for positively retracting said armature still farther from its electromagnet and for maintaining said armature in retracted position while the engine is running.

14. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means including a centrifugal switch responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch to open, and means acting directly upon said rod in response to engine operation for positively retracting said armature still further from its electromagnet and for maintaining said armature in retracted position while the engine is running.

15. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means including a second electromagnet coil responsive to E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampere-turn effect of the first coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch 'to open, and means acting directly upon said rod in response to engine operation for positively retracting said armature still farther from its electromagnet and for maintaining said armature in retracted position while the engine is running.

16. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means including a centrifugal switch responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch to open, a generator for charging the battery and an electromagnet responsive to generator voltage and having an armature attached to said rod and operable to move said rod in a direction to retract said first mentioned armature still farther from its electromagnet and to maintain said first mentioned armature in retracted position while the engine is running.

1'7. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means including a second electromagnet coil responsive to E. M. F. of the armature of the starting motor when over-speeding for cancelling the ampere-tum effect of the first coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch to open, a generator for charging the battery and an electromagnet responsive to generator voltage and having an armature attached to said rod and operable to move said rod in a direction to retract said first mentioned armature still farther from its electromagnet and to maintain said first mentioned armature in retracted position while the engine is running.

18. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch including a movable contact, an electromagnet for closing the starter switch and including a coil and a movable armature, an endwise movable rod connecting the armature and movable contact, a spring normally holding the armature in a position retracted from its electromagnet, a switch for connecting said coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil thereby permitting said armature to be retracted by said spring from its electromagnet and the switch to open, a generator for charging the battery and an electromagnet responsive to generator voltage and having an armature attached to said rod and operable to move said rod in a direction to retract said first mentioned armature still farther from its electromagnet and to maintain said first mentioned armature in retracted position while the engine is running.

19. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and inculding a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil to permit opening of starter switch, means responsive to engine operation for positively holding the starter switch in open position, and means for retarding movement of the armature.

- 20. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch, an electromagnet for closing the starter switch and including a coil and a movable armature for actuating the movable contact of the starter switch, a switch for connecting said coil with the battery, means responsive to over-speeding the starting motor for weakening the influence of said coil to permit opening of starter switch, a generator having a shunt field directly excited by the battery and means responsive to generator voltage for positively holding the starter switch in open position.

21. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the force exerted by said means on said switch, means controlled by the speed of the starting motor itself for operating said control switch, and means operated by the engine for holding the starter switch open when the engine is running under its own power.

22. An engine starter control system compris ing, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the force exerted by said means on said switch, means controlled by the speed of the starting motor for operating said control switch to decrease the force exerted by said holding means on said starter switch as the starting motor speed increases to permit opening of the starter switch, and means operable by the engine for holding the starter switch open during operation of the engme.

23. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for.

holding said switch closed, a control switch for regulating the force exerted by said means on said switch, means controlled by the speed of the starting motor for operating said control switch to decrease the force exerted by said holding means on said starter switch as the starting motor speed increases to permit opening of the starter switch,"

and means responsive to operation of the generator for holding said starter switch open while the engine is running.

24. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the force exerted by said means on said switch, means controlled by the starting motor and operable when said motor reaches a predetermined speed for reducing the force exerted by said holding means to permit opening of the starter switch, and means operable by the engine for holding the switch open when the engine is in operation.

25. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, a magnet for holding said switch closed, a control switch for regulating the force exerted by said magnet to hold said starter switch closed, means controlled by the speed of the starting motor for operating said control switch to decrease the iorce exerted by said magnet on said starter switch to permit opening of said switch, and means operable by the engine for holding said starter switch open during operation of the engine.

26. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, a magnet for holding said switch closed, a'control switch for regulating the force exerted by said magnet to hold said starter switch closed, means controlled by the speed of the starting motor and operable when the starting motor reaches a predetermined speed for operating said control switch to decrease the force exerted by said magnet on said starter switch to permit opening of said switch and means operable by the engine for holding said starter switch open during operation of the engine.

2'7. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection oi the starting motor with the battery, a magnet for holding said switch closed, a control switch for regulating the force exerted by said magnet to hold said starter switch closed, means controlled by the speed of the starting motor for operating said control switch to decrease the force exerted by said magnet on said starter switch to permit opening of said switch, and means responsive to operation of the generator for holding said starter switch open during engine operation.

28. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the operation of said holding means on said switch, means controlled by the speed of the starting motor itself for operating said control switch, and means operated by the engine for holding the starter switch open when the engine is running under its own power.

' 29. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the operation of said holding means on said switch, means controlled by the speed of the starting motor for operating said control switch to effect opening of the starter switch on increase in speed of the starting motor, and means operable by the engine for holding the starter switch open during operation of the engine.

30. An engine starter control system comprising, in combination, a battery, a starting motor, a starter switch for controlling the connection of the starting motor with the battery, means for holding said switch closed, a control switch for regulating the operation of said holding means on said switch, means controlled by the speed of the starting motor for operating said control switch to'efiect opening of the starterswitch, and means responsive to operation of the generator for holding said starter switch open while the engine is running.

31. An engine starter control system comprising, in combination, a current source, a starting motor and means for controlling the operation of said starting motor comprising a main starter switch for directly controlling the connection of the starting motor with the current source, a control switch for controlling the operation of said main switch, means operable upon increase of speed of the starting motor for operating said control switch, a generator, and means whereby operation or the generator directly controls the operation of said main switch.

32. An engine starter control system comprising, incombination, a current source, a starting motor and means for controlling the operation of said'starting motor comprising a main starter switch for directly controlling the connection of the starting motor with the current source, a. control switch for controlling the operation of said main switch, means operable upon increase of speed of the starting motor for operating said control switch, a generator, means whereby operation of the generator directly controls the operation of said main switch, and means whereby the opening of the control switch causes the generator to become effective to open the main switch.

JOHNB. DYER. 

